. >>> today pope benedict xvi surprised the world by becoming the first pontiff in more than 700 years to abdicate as head of the catholic church. nbc joins us live from rome. we know that the pope's doctor had advised him against taking any more transatlantic trips. but is there any specific illness or condition that may have led the pope to make this announcement just apart from his age? >> reporter: well, martin, there was a lot of speculation, of course, about what was really behind this decision, and a spokesperson this morning during a press conference he called after he said he didn't even know about his abdication, he just called this press conference and said, look, the pope is not ill or he doesn't have any particular illness and there's nothing behind his decision apart from what he said, which is he's really too tired to carry on with the duties as a pontiff and as an 85-year-old man, any 85-year-old man will find it harsh to go through a schedule like the one the pope has to go through during his pontiff cat. if you think about the number of trips he's taking, the neck one